kwin: Detect and handle graphics resets

Reset compositing when the GL context state has been lost as a result
of a graphics reset.

composite.cpp

@@ -198,6 +198,7 @@ void Compositor::slotCompositingOptionsInitialized()
 #endif
 
             m_scene = SceneOpenGL::createScene();
+            connect(m_scene, SIGNAL(resetCompositing()), SLOT(restart()));
 
             // TODO: Add 30 second delay to protect against screen freezes as well
             unsafeConfig.writeEntry(openGLIsUnsafe, false);

kwin.notifyrc

@@ -194,3 +194,8 @@ Comment[x-test]=xxAnother application has requested to suspend compositing.xx
 Comment[zh_CN]=另一个应用程序已经请求中断混成操作。
 Comment[zh_TW]=另一個應用程式要求暫停組合效能。
 Action=Popup
+
+[Event/graphicsreset]
+Name=Graphics Reset
+Comment=A graphics reset event occurred
+Action=Popup

scene_opengl.cpp

@@ -46,6 +46,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "workspace.h"
 
 #include <math.h>
+#include <unistd.h>
 
 // turns on checks for opengl errors in various places (for easier finding of them)
 // normally only few of them are enabled
@@ -64,6 +65,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <QMatrix4x4>
 
 #include <KDE/KLocalizedString>
+#include <KDE/KNotification>
 #include <KProcess>
 
 namespace KWin
@@ -275,6 +277,48 @@ void SceneOpenGL::copyPixels(const QRegion &region)
 }
 #endif
 
+#ifndef KWIN_HAVE_OPENGLES
+#  define GL_GUILTY_CONTEXT_RESET_KWIN    GL_GUILTY_CONTEXT_RESET_ARB
+#  define GL_INNOCENT_CONTEXT_RESET_KWIN  GL_INNOCENT_CONTEXT_RESET_ARB
+#  define GL_UNKNOWN_CONTEXT_RESET_KWIN   GL_UNKNOWN_CONTEXT_RESET_ARB
+#else
+#  define GL_GUILTY_CONTEXT_RESET_KWIN    GL_GUILTY_CONTEXT_RESET_EXT
+#  define GL_INNOCENT_CONTEXT_RESET_KWIN  GL_INNOCENT_CONTEXT_RESET_EXT
+#  define GL_UNKNOWN_CONTEXT_RESET_KWIN   GL_UNKNOWN_CONTEXT_RESET_EXT
+#endif
+
+void SceneOpenGL::handleGraphicsReset(GLenum status)
+{
+    switch (status) {
+    case GL_GUILTY_CONTEXT_RESET_KWIN:
+        kDebug(1212) << "A graphics reset attributable to the current GL context occurred.";
+        break;
+
+    case GL_INNOCENT_CONTEXT_RESET_KWIN:
+        kDebug(1212) << "A graphics reset not attributable to the current GL context occurred.";
+        break;
+
+    case GL_UNKNOWN_CONTEXT_RESET_KWIN:
+        kDebug(1212) << "A graphics reset of an unknown cause occurred.";
+        break;
+
+    default:
+        break;
+    }
+
+    QElapsedTimer timer;
+    timer.start();
+
+    // Wait until the reset is completed or max 10 seconds
+    while (timer.elapsed() < 10000 && glGetGraphicsResetStatus() != GL_NO_ERROR)
+        usleep(50);
+
+    kDebug(1212) << "Attempting to reset compositing.";
+    QMetaObject::invokeMethod(this, "resetCompositing", Qt::QueuedConnection);
+
+    KNotification::event("graphicsreset", i18n("Desktop effects were restarted due to a graphics reset"));
+}
+
 qint64 SceneOpenGL::paint(QRegion damage, ToplevelList toplevels)
 {
     // actually paint the frame, flushed with the NEXT frame
@@ -285,6 +329,13 @@ qint64 SceneOpenGL::paint(QRegion damage, ToplevelList toplevels)
     }
 
     m_backend->prepareRenderingFrame();
+
+    const GLenum status = glGetGraphicsResetStatus();
+    if (status != GL_NO_ERROR) {
+        handleGraphicsReset(status);
+        return 0;
+    }
+
     int mask = 0;
 #ifdef CHECK_GL_ERROR
     checkGLError("Paint1");

scene_opengl.h

@@ -80,8 +80,14 @@ protected:
     QMatrix4x4 transformation(int mask, const ScreenPaintData &data) const;
     virtual void paintDesktop(int desktop, int mask, const QRegion &region, ScreenPaintData &data);
 
+    void handleGraphicsReset(GLenum status);
+
     virtual void doPaintBackground(const QVector<float> &vertices) = 0;
     virtual SceneOpenGL::Window *createWindow(Toplevel *t) = 0;
+
+Q_SIGNALS:
+    void resetCompositing();
+
 public Q_SLOTS:
     virtual void windowOpacityChanged(KWin::Toplevel* c);
     virtual void windowGeometryShapeChanged(KWin::Toplevel* c);